MainActivity.java

public class MainActivity extends Activity implements MainPresenter.View {
  MainPresenter mainPresenter;
  RecyclerView.Adapter adapter;
  @Override public void onCreate(Bundle savedInstance) {
    RecyclerView rv = findViewById(R.id.lv);
    adapter = new SampleAdapter();
    rv.setAdapter(adapter);
    
    mainPresenter = new MainPresenter(this);
    
    mainPresenter.initData();
  }
  
  @Override public void addDatas(List<Data> datas) {
    for (Data data : datas) {
      adapter.add(data);
    }
    adapter.notifyDatasetChanged();
  }
  
  private static class SampleAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
    List<Data> datas;
    SampleAdapter() {
      datas = new ArrayLst<Data>();
    }
    
    public void add(Data data) {
      datas.add(data);
    }
    
    // ...
    
  }
}

MainPresenter.java

public class MainPresenter {
  
  private MainPresenter.View view;
  public MainPresenter(MainPresenter.View view ) {
    this.view = view;
  }
  
  public void initData() {
    List<Data> datas = new ArrayList<Data>();
    datas.add(new Data());
    datas.add(new Data());
    view.addDatas(datas);
  }
  
  public interface View {
    void addDatas(List<Data> datas);
  }
}